Breakthrough: New Carbon Nanotube Solar Cells Capture Infrared Light

Conventional silicon-based solar cells do not capture the 40 percent or so of solar energy that is in the infrared region of the light spectrum. However, now a new all-carbon solar cell has been developed by researchers at MIT, which can convert that previously unused solar energy.

This new innovation opens up the possibility of developing solar panels that could use both traditional silicon-based cells and carbon cells to capture nearly the whole range of solar energy.

The new solar technology innovation has been described in the journal Advanced Materials. Senior author of the paper Prof. Michael Strano from MIT has said, “It’s a fundamentally new kind of photovoltaic cell”. The innovative cell is made from carbon nanotubes and carbon C60 (a.k.a. buckyballs), and is the first all-carbon photovoltaic cell.

The researchers have said that because the carbon-based cells are transparent to visible light, they could be placed on top of conventional solar cells, making solar panels that would be able to use most of the energy from the Sun. However, as with most innovations in the lab, the current proof-of-concept will need refining. The energy-conversion efficiency is currently only around 0.1 percent. Nonetheless, the researchers have said they are very much on track to creating very high efficiency near-infrared solar cells.

One major advantage of the new cells is that relatively small amounts of highly purified carbon would be used, and the cells would weigh very little. Because the light absorption of carbon nanotubes is very high, not a lot of material is needed to absorb a great deal of light.